AUTHOR=Liu Dong , Lin Liang , Zhang Tie , Xu Qian , Wang Mulan , Gao Minghai , Bhople Parag , Pritchard Hugh W. , Yang Xiangyun , Yu Fuqiang 

TITLE=Wild Panax plants adapt to their thermal environment by harboring abundant beneficial seed endophytic bacteria

JOURNAL=Frontiers in Ecology and Evolution

VOLUME=10

YEAR=2022

URL=https://www.frontiersin.org/journals/ecology-and-evolution/articles/10.3389/fevo.2022.967692

DOI=10.3389/fevo.2022.967692

ISSN=2296-701X

ABSTRACT=<p>The seed microbiome of crop wild relatives is a potential reservoir of beneficial traits that potentially improve their host plant resilience to fluctuating environments and pathogenic threats. Herein, we studied the seed microbiome of three species of the medicinal genus <italic>Panax</italic> (<italic>P. vietnamensis</italic>, <italic>P. japonicas</italic>, and <italic>P. stipuleanatus</italic>) collected from seven locations in Southwest China. We used qPCR and metabarcoding high-throughput sequencing to target both endophytic bacteria and fungi. Seed bacterial absolute abundance (1.1 × 10<sup>9</sup>∼1.0 × 10<sup>7</sup> gene copy numbers per gram seed) was substantially higher than that of fungi (7.6 × 10<sup>5</sup>∼3.7 × 10<sup>2</sup>). Host plant genotype was the main driver of seed microbiome composition for both bacteria and fungi. <italic>Panax</italic> growing hypothermal environments significantly shaped their seed endophytic bacterial but not fungal microbiota. The three <italic>Panax</italic> species’ seeds harbored unique microbes [averaged ∼150 amplicon sequence variants (ASVs)], sharing only 12 bacterial ASVs (half affiliated to <italic>Halomonas</italic>) and four fungal ASVs. Network analysis showed that the <italic>Panax</italic> seed endophytic bacteria tend to form inter-weaved functional modules that are majorly connected by core members from the genus <italic>Halomonas</italic>, <italic>Pseudomonas</italic>, and <italic>Pantoea</italic>. These genera have been associated with nutrient cycling, plant, disease suppression, and tolerance to environmental fluctuation. Together, these novel insights may shade light on the ecological strategies of wild <italic>Panax</italic> plants adaptation to their thermal environment by possessing abundant beneficial seed endophytic bacteria.</p>